don't worry that much because it's pretty normal to have such reaction espcially that it's still fresh. You have to address what you feel right now and entertain it. After all, a year and 8 months is quite a long time. If you truly had feelings for him, then you would feel such. It reaffirms your feeling that you really loved her.
Now, how do you cope up with it? Let it be. You can't do anything about it for now. You don't have any hold of her any longer for you're not an item. If you can cry it out, go on right ahead. It does help rather than keeping it inside. Let it out. It's like a therapy to help you with the loss. Soon enough you'd feel a little better. Then you can start looking for a girl.
Make a constant effort to give yourself some time to heal from the loss. And someday, even if you see her with a million men, you can say to youreself, "I DON'T GIVE A DAMN!!"